: The Comorbidity and Addiction Center (CAC) for social work research development seeks five years of support for a predoctoral and postdoctoral research training program focusing on services and treatment of substance abusing and comorbid populations. This Social Work Training in Addictions Research (STAR) program will produce well-trained social work researchers who are knowledgeable about the need for addictions services (particularly in underserved populations), evaluation of prevention and interventions, and the costs and burdens of addictions in specialty and nonspecialty services delivery systems. Our predoctoral and postdoctoral trainees will learn the skills needed to develop significant research projects, to publish results, and create strong grant applications, We will train students to conceptualize problems and questions for study, design research studies, understand and carry out data management and analysis, write for publication and proposal development, and collaborate on interdisciplinary research teams. Our trainees will learn these skills through (a) interdisciplinary and specialized coursework taught by leading faculty from social work, psychiatry, economics, statistics, and the social sciences; (b) experience on funded substance abuse treatment services research through three predoctoral semesters of required research practicurn and, in other semesters, through research assistantships; (c) pilot study work groups provided through the Comorbidity and Addictions Center; (d) structured mentoring and advising by a CAC preceptor in their area of focus; (e) guided experiences in grant writing, professional presentations, and manuscript preparation; (f) a required two year long special addictions seminar co-taught by the CAC directors, faculty, collaborators, and consultants; and (g) predoctoral teaching assistantships in Master?s courses on addiction, comorbidity, and research methodology. Both predoctoral and postdoctoral trainees will participate in national research conferences as learners and as presenters; and will co-author at least one scholarly publication with their mentor. In addition, they will participate in the preparation of proposals based on CAC faculty pilots. Postdoctoral trainees will be mentored to submit R03 and R01 applications. This will give them a practiced understanding of writing research proposals for external funding. Predoctoral trainees will be prepared to move directly into postdoctoral research programs in addictions research or into research and faculty positions at schools of social work. Postdoctoral trainees will be prepared to move directly into research or faculty positions. There they will advance knowledge and teach the next generation of social work addictions service providers and researchers. These program graduates will be able to compete with the best scholars in obtaining peer reviewed funding for significant research in the field.